Justification:Bothrops insularis is known only from one location: a small island off southeastern Brazil (total area 43 ha). The species' highly restricted range and continuing decline in habitat quality, as a result of removal of vegetation by people from the Brazilian Navy who keep the lighthouse, qualify it for the Critically Endangered category.

The main threat to the species is the destruction of habitat. Large areas of the island have been destroyed through repeated burning. The continuation of such activities threaten the survival of the species.